The DesignLights Consortium™
(DLC) is a collaboration of utilities and energy efficiency organizations to accelerate energy efficiency measures in commercial buildings. The rebate process that many utilities use requires DLC qualified products to be installed and substantial energy savings realized. As part of the lighting rebate process, the DLC List is the first step in examining outdoor lighting and other projects for rebate eligibility. The DLC list requires LED fixture manufacturers submit test results from certified labs on the luminaires to be qualified, or 'listed' by the DLC. The reports submitted for the DLC qualification process include the LM-79 report that quantifies the LED fixtures performance, as well as, the LM-80 report that examines the actual LED light engine and uses TM-21 methods to project LED lifetimes. By submitting these reports and undergoing the DLC Qualification Process, assures that the Manufacturer of LED lighting products, have met certain minimum specifications for performance, as well as reassurance to the buyer.
DLC List - Specifications for Outdoor and other LED Lighting
For people procuring LED light fixtures, being on the DLC Qualified Product List, assures that the LED outdoor lighting manufacturer specifications have been reviewed and meet minimum performance parameters. The main DLC Qualified Product List performance specifications include:
Minimum light output (lumens) from the LED fixture based on lighting application type
Zonal Lumens - How the light output is distributed from the fixture to its lighting task
Minimum luminous efficiency - How many watts of energy does it take to produce light in lumens per watt
Correlated Color Temperature (CCT) - A measure of how the light appears from warm colors like incandescent at a 1,600K CCT to noon bright white at 5,000K CCT.
Color Rendering Index - An indication of how color appears under reflected light of the LED fixture. Typical HID metal halide ratings are in the CRI 60 range, incandescent light by definition is a CRI of 100.
Lumen Maintenance (L-70) is a projected value of when an LED light source will produce 70% of its original light output. It is listed in hours and the accepted value for the end-of-life for an LED fixture. An L-70 lifetime rating is temperature dependent and is usually listed at 25° C. An L-70 lifetime of 50,000 hours at 12 hours per day of LED fixture use is 11.4 years of outdoor lighting fixture use.
Warranty - The DLC requires some more tea of five years
DLC List and Rebates for LED Outdoor Lighting
LED lighting rebates are most often offered by Electric Utilities, and sometimes by State grant making organizations. Rebates are highly variable, and have many different requirements to be eligible for rebates. But in general, a product that is qualified on the DLC List is a good indication that rebates for outdoor lighting can be obtained. A good first source for finding rebate information is the DSIRE
(Database of State Incentives for Renewables & Efficiency).
Outdoor lighting rebates are generally of two types, qualified product rebates and performance based programs. Qualified product rebates are most often a rebate of a fixed amount per fixture replaced, while the performance based programs are based on the kilowatt hours or peak kilowatts of load electricity saved.
Rebate Process for LED Outdoor Lighting
Determination of which option is optimal in obtaining outdoor lighting rebates will require a modest amount lighting design and economic analysis. In overview, the rebate process involves:
- Inventorying existing HID lighting fixtures,
- Determine what lighting levels are required for the outdoor lighting application,
- Selecting LED fixture will meet these lighting requirements at the lowest possible energy use
- Compiling a spreadsheet of existing lighting fixtures compared to the proposed fixtures
Most utilities will require a spreadsheet that lists what HID fixture is being replaced with what DLC Listed product. The spreadsheet will often articulate the savings per fixture count, application type (e.g. garage lighting), and the total kilowatt hours saved and the load reduction in kilowatts.
Based on this information the utility can quickly qualify the LED lighting installation for rebates, and give a general indication of the rebate amounts and levels. After the project is installed, most often certifications are required by the property owner that the installation has been completed, and in some cases, a site inspection will take place. The Utility or other rebate grantor will then mail a check to the property owner for the agreed rebate amount.